The damning interim report published by HM Inspectorate of Constabulary identified “serious concerns” about how crime was being recorded in a number of forces.

A total of 14 rapes were among the offences not recorded by officers, including an allegation made by a 13-year-old autistic boy written off as “sexual experimentation”.

Another rape was not recorded due to “workload pressure” as recording the crime would “entail too much work”, the report said.

The police watchdog also found some offenders have been issued with out-of-court disposals, such as cautions, when they should have been prosecuted.

And inspectors said they could not rule out “discreditable or unethical behaviour” on the part of officers for the failure rate.

Essex Police was one of 13 forces inspected by HMIC, which will report on all 43 forces this October. Yesterday Essex Police said they welcomed the report.

Essex Police was not the worst force examined in the report, of 120 crimes inspected by HMIC that should have been recorded, 110 were recorded. Furthermore of 73 no-crime decisions that were reviewed, only five were found to be incorrect.

However HM Chief Inspector of Constabulary Tom Winsor emphasised that these samples on their own are too small to be statistically significant, and only the overall figure could be replied upon.

Mr Winsor said: “The consequences of under-recording of crime are serious, and may mean victims and the community are failed because crimes are not investigated, the levels of crime will be wrongly under-stated, and police chiefs will lack the information they need to make sound decisions on the deployment of their resources.

“Although this is an interim report, and we have identified common strengths, we are seriously concerned at the picture which is emerging – particularly about the significant under-recording of crime, and serious sexual offences not being recorded.”

Nick Alston, Police and Crime commissioner for Essex, said there were “robust processes that exist in Essex Police to ensure that crimes are correctly recorded, enabling informed and intelligent decisions to be made around the deployment of our police officers, PCSOs and police staff.”

He added: “I am also convinced that moving away from a slavish reliance on strict performance targets, of a lazy culture of ‘chasing the figures’, is important in helping to ensure crime is recorded ethically.”

“We understand the importance of accurate crime data, both in terms of the service we deliver to victims of crime and in the investigation of offences. Public confidence in what we do sits at the heart of what Essex police stands for.

“We will continue to apply rigorous standards to our audit process as there is always room for further improvement.”

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